Although the epidemiology of infections in acute care hospitals has been thoroughly examined, such is not the case for nursing homes. Prevalence studies of infections in these facilities provide conflicting data and give little description of the elderly populations at risk. No incidence data for infections in nursing homes is available. Without these data a detailed analysis of the importance of predisposing and causal factors is difficult. We intend to demonstrate that infections in nursing home patients reduce quality of life as measured by activities of daily living and result in hospital admissions, death, and measureable cost. Over a two year period we will measure the incidence of these infections and the magnitude of the associated morbidity in two large nursing homes providing different levels of care. We will examine the association of onset of infection with potential risk factors: level of activity and awareness; continence of urine or stool; nutritional status; alimentary or urinary tract instrumentation; and use of hypnotics or steroid medication. We will then determine whether these associations apply to nursing homes of different size and location in the State of Maryland. We will measure the prevalence of infection and of potential risk factors in a stratified random sample of these homes. In addition, we will determine whether the prevalence of infection in nursing homes varies by the level of patient care provided and the number and training of nursing home personnel in relation to the number of patients. The goals of this project are to define those infections causing the greatest morbidity and mortality in nursing home patients, to determine the importance of selected risk factors for those infections and, thereby, to direct the subsequent design of intervention trials for those risk factors which appear to be alterable.